(CNN) -- The search for a plane that was carrying a software company president and members of his family when it disappeared from radar over Idaho was set to resume Wednesday morning after would-be rescuers were forced to suspend their efforts because of nightfall, authorities said.
Search and rescue teams detected a weak signal from an emergency locator transmitter that allowed authorities to narrow the search to the area south of Johnson Creek, near Yellow Pine, where the plane is believed to have gone down.
"We've done a ping on the cell phones, and we've narrowed it down to a 4- or 5-square-mile area that we're searching right now," Valley County Sheriff's Office Lt. Dan Smith told CNN affiliate KGO.
Dale Smith had left Baker City, Oregon, with his son, his son's wife, his daughter and her fiance, said Rand Kriech. He and Smith founded SerialTek, a San Jose, California, company that develops hardware and software data storage tools.
Smith's wife and another daughter were in Cascade, Idaho, on Tuesday awaiting news about the search, Kriech said.
The Smiths were in Dale Smith's single-engine Beechcraft Bonanza en route to Butte, Montana. About 3 p.m. Sunday, as they were flying over central Idaho at an altitude of 9,000 feet, the 51-year-old executive reported engine trouble and asked controllers in Salt Lake City for the coordinates of the Johnson Creek Air Strip, the sheriff's spokesman said.
They never made it.
Snow hampered search efforts, carried out Monday by helicopters from the Idaho Army National Guard.
Three more planes were expected to join the search on Wednesday, according to Robert Feeley, a spokesman for the Idaho Bureau of Homeland Security.
About 40 search and rescue teams, some using ATVs and snowmobiles, combed the area Tuesday and were expected to resume their efforts at first light on Wednesday, authorities said.
Repeated attempts to fly into the area of the last known contact, about a mile east of the Johnson Creek Air Strip, were unsuccessful Monday because of poor weather, the Valley County Sheriff's Office said.
"If there is anyone who is able to survive a difficult situation, that would be Dale," San Jose Mormon Bishop Jed Dyreng told KGO of his fellow churchgoer. "When there was Hurricane Katrina, Dale was the first one to get in his plane, grab a bunch of members of his church and go out and help."
"We are a little bit worried," said the bishop's wife, Ann Dyreng, who flew with Smith to Utah in October. "He's an engineer brain, and he's very meticulous about doing all that. He's meticulous in all things he does."
Smith co-founded SerialTek in 2007, serving as president and chief technologist. It employs 25 people, said Kriech, who described Smith as a religious man who had done humanitarian work with the group Medecins sans Frontieres.
"He's an engineer's engineer," Kriech said Tuesday. "If anyone can get out of this situation, it's Dale. Hopefully, he laid the plane down safely. That's what we are hoping and praying for this morning. He's a good man, and we're hoping to see him back here."
CNN's Chuck Johnston contributed to this report.